ESSENDON is confident midfielder Dyson Heppell will be available for round one, despite undergoing knee surgery on Tuesday that will sideline him for up to three weeks.

Heppell, who complained of soreness during Tuesday's main training session, underwent a successful operation on his left knee later that afternoon.

Club doctor Bruce Reid said the 22-year-old remained on track to face the Sydney Swans in the Dons' season opener on April 4.

"Dyson’s surgery was successful, Julian Feller removed a flap of surface cartilage from his left knee," Reid told the club's website.

"The process moving forward is to let Dyson’s knee settle over the next two weeks.

"We will continue to monitor Dyson during this period and all going well he will be able to commence training in a fortnight." 

Heppell is among the Essendon players not taking part in the NAB Challenge until the AFL Anti-Doping Tribunal has reached a decision regarding the club's 2012 supplements program.

Meanwhile, defender Courtney Dempsey had to sit out Wednesday's training session after straining his plantar facia on Monday.

But Bombers doctor Brendan De Morton said the injury was not a major concern and he was confident Dempsey would be back training next week.

“He’ll be off his feet until Monday and then we’ll crank him up from there,” he told the club’s website.

“I’d be hopeful he’ll be into full training by mid next week.”

Dyson Heppell is a $606,000 midfielder in NAB AFL Fantasy this year. Set up a live draft and take on your mates in Fantasy Elite now.

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